In Windows 10 Technical Preview for PC, you may face with the error coded 0x80070103.

Windows 10 error 0x80070103
Windows 10 error 0x80070103
How to fix it? Please read the instruction below to solve this issue.

First, please answer this question to get more clarity on this issue.
  • On which Windows Update KB number do you get this error message?
This issue might occur if some system files associated with the Windows Update are not working as expected.
Sorry to know that you are facing this issue.
Follow these steps to view installed updates:
  • Press “Windows key + X” and click on “Programs and Features”.
  • Click on “View Installed Updates”. Let us know the recent update after which you are facing this issue.
You will be able to solve some problems by running a troubleshooter that will automatically fix some common issues with Windows Update.
Open the Windows Update troubleshooter by swiping in from the right edge of the screen, tappingSearch (or if you’re using a mouse, pointing to the upper-right corner of the screen, moving the mouse pointer down, and then clicking Search), entering Troubleshooting in the search box, tapping or clickingSettings, and then tapping or clicking Troubleshooting. Under System and Security, tap or click Fix problems with Windows Update.
Refer to this article to know more.
Further, you may boot the computer in a clean boot state and try to install the updates to check if this helps. When you start Microsoft Windows, typically there are several programs that start automatically and run in the background that may interfere with the program. These programs may include antivirus and system utility programs. When you perform a clean startup procedure, you prevent these programs from starting automatically.
How to troubleshoot a problem by performing a clean boot in Windows: (Applies to Windows 10)http://support.microsoft.com/kb/929135
Note: After you have finished troubleshooting, follow steps under “How to reset the computer to start as usual after troubleshooting with clean boot” in the article to boot to normal startup.
Ensure to keep the computer up to date with all Windows Updates. Windows Update is a package which provides a collection of performance and reliability improvements. Windows Update helps keep your PC safer—and your software current—by fetching the latest security and feature updates from Microsoft via the Internet.
Important updates help improve the security of Windows and your computer, and they should be installed. Optional updates often are updated device drivers or program updates that aren’t critical to their operation. You can install optional drivers if they add features (such as additional languages) or if you are having problems with an existing device or program.
To “check for updates” for other software programs and devices that do not appear in Windows Update, go to the software publisher’s or manufacturer’s website.
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